Container seal

ABSTRACT

A seal for a container of fine particulate materials that includes a sifter insert. The seal comprises a base that is secured over a plurality of holes in the insert by a releasable pressure-sensitive adhesive. A pull tab extends outwardly from an upper surface of said base. The pull tab is fixedly adhered to the upper surface of the base and extends outwardly away from a mid-section thereof. The pull tab is pivotable through 180 degrees about its connection point with the base and remains fixedly secured thereto when a pulling force is applied to the pull tab. The adhesive bond between the base and the insert is weaker than the adhesive bond between the pull tab and the base. Consequently, a pulling force applied to the pull tab removes the base from the insert and permits particulate material to be dispensed through the holes in the insert.

BACKGROUND OF THE INVENTION

1. Technical Field

The invention relates to containers and to methods for sealing the same. More particularly, the invention relates to a seal for a container for particulate material. Specifically, the invention relates to a pressure sensitive pull tab seal for containing a particulate material within a container until such containment is no longer required.

2. Background Information

Transportation of fine particulate materials or powders creates challenges in containing the substance in such a way that, when the material is to be accessed, it is in a usable and undisturbed condition. Disturbing a particulate material that is not contained properly can result an irreversible airborne dispersion of the particulate material. The fine particles will fill any void or free space if not contained properly.

The simplest form of containing a fine particulate material is through the use of a lid or stopper to close the container. Depending on the desired use of the particulate material, the stopper can be solid and removable by the user to expose the entire supply of material. Alternatively, the stopper may be fixed and non-removable with holes therein through which the particulate material can be dispensed at a controlled rate. The stopper with holes is a type of insert so the material can be dispersed as desired by the user.

When using an insert-type of stopper the holes therein have to be sealed in some manner in order to keep the material within the container until the particulate material is to be dispensed. The simplest form of sealing an insert-type stopper is to place a cap over the stopper to seal the container. However, the fine particulate material will travel through the insert holes and accumulate in the space between the stopper and the cap and will not be completely contained in the chamber. Alternatively, a removable seal may be placed over the mouth of the container and between the chamber and the insert-type stopper. The user then has to remove the stopper in order to access the seal, remove the seal and replace the insert on the container prior to dispensing the particulate material.

Seals typically aren't placed directly onto the top surface of an insert-type of stopper to seal the holes therein. There are a number of reasons for this. Firstly, hot-melt structural adhesives are typically used on seal backings because they form strong bonds with the adherent. These bonds are difficult to break evenly and consistently around the seal. Consequently, when the seal is removed a quantity of residual adhesive and seal debris remain on the insert stopper. When particulate materials are dispensed from the container, a quantity of the particulate material will accumulate on the adhesive residue and potentially block the holes in the insert. Furthermore, this adhesive residue contaminates the particulate material and reduces the benefit of using an insert style container. Secondly, in addition to the adhesive residue left on the insert-style stoppers, another problem occurs when trying to remove a container seal from directly over the insert holes. Removal of the seal must begin at the side of the seal to start breaking the bond of the adhesive. Oftentimes the cavity walls in the container mouth leave little room for a user to gain a secure hold on the seal. Some previously known seals have incorporated a small detent that extends outwardly from the seal's peripheral edge for the user to grasp. Typically, these detents are so small and the space limitations are problematic enough that the user cannot adequate grasp the detent to begin removing the seal. Users are consequently forced to use fingernails, scissors, knives, and other scraping devices to start peeling the seal back from the stopper. Some users have even resorted to poking holes with sharp instruments through the seal and into the insert holes. The scraping and poking of holes through the seal and insert holes tends to cause mixing of the particulate material with residue from the adhesive and seal, thus the fine particulate material.

Thus, the need exists in the art for an easily removable seal for an insert-style container that leaves little to no residue on the container's insert stopper after removal therefrom.

BRIEF SUMMARY OF THE INVENTION

A seal for a container of fine particulate materials that includes a sifter insert. The seal comprises a base that is secured over a plurality of holes in the insert by a releasable pressure-sensitive adhesive. A pull tab extends outwardly from an upper surface of said base. The pull tab is fixedly adhered to the upper surface of the base and extends outwardly away from a mid-section thereof. The pull tab is pivotable through 180 degrees about its connection point with the base and remains fixedly secured thereto when a pulling force is applied to the pull tab. The adhesive bond between the base and the insert is weaker than the adhesive bond between the pull tab and the base. Consequently, a pulling force applied to the pull tab removes the base from the insert and permits particulate material to be dispensed through the holes in the insert.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The preferred embodiments of the invention, illustrative of the best modes in which Applicant has contemplated applying the principals of the invention, are set forth in the following description and are shown in the drawings.

FIG. 1 is an exploded perspective view of a container seal system according to the present invention;

FIG. 2 is a perspective view of the container with the paper seal exploded away therefrom to expose the container insert;

FIG. 3 is cross-sectional front view of the container with the seal applied to the insert;

FIG. 3A is an enlarged cross-sectional front view of the highlighted region of FIG. 3;

FIG. 4 is a cross-sectional side view of the container taken through line-4-4 of FIG. 3 and showing the user grasping the seal tab to remove the same from the container;

FIG. 5 is a cross-sectional side view of the container showing the pull tab and seal partially removed from the insert; and

FIG. 6 is a cross-sectional side view of the container showing the pull tab and seal entirely removed from the container.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-6, there is shown a container system in accordance with the present invention and generally indicated at 1. Container system 1 is described with reference to a container specifically for a cosmetic powder. It will be understood, however, that system 1 can be any container system that retains a quantity of fine particulate material 22 therein. The particulate material 22 may be talcum powder, paint powder, toner powder etc. It will further be understood that the container and insert can be of any shape, size or configuration, without departing from the spirit of the present invention.

Container system 1 comprises a container 6, a lid 2, an insert 14, and a cosmetic applicator 4. Container 6 is generally cylindrical in cross-section and includes a bottom wall 6 a, a peripheral side wall 6 b extending upwardly away from bottom wall 6 a, and an upper wall 6 c that terminates in a downwardly extending flange 6 d and lip 7. Bottom, side and upper walls 6 a, 6 b, 6 c surround and define an interior chamber 21 that receives and retains a quantity of particulate material 22 therein. Lip 7 defines an annular opening 9 through which the chamber 21 is accessible.

An insert 14 is provided to block opening 9 and limit access to chamber 21. Insert 14 comprises a bottom wall 14 a and a peripheral side wall 12 extending upwardly away therefrom. Peripheral side wall 12 terminates in an annular flange 11 which is complementary in shape and size to flange 6 d and lip 7 on container 6. Flange 11 interlocking engages flange 6 d and lip 7 on container 6 when insert 14 is press fitted into opening 9. The bottom and side walls 14 a, 12 of insert 14 surround and define an interior cavity 10. Bottom wall 14 a of insert 14 further defines a plurality of insert holes 16 therethrough. Holes 16 provide a plurality of small passageways through which particulate material 22 may be dispensed from interior cavity 21 of container 6.

In accordance with a specific feature of the present invention, a seal 8 is provided to close off holes 16 in bottom wall 14 a of insert 14 subsequent to manufacture and prior to use. Seal 8 comprises a base 18, an undertab layer 26 and a laminate layer 28. Base 18 preferably is a pressure sensitive paper manufactured from 60# semi-gloss paper coated with TR-1 ultra-removable pressure sensitive adhesive applied thereto. The paper is made by Technicote, Inc. of Cuyahoga Falls, Ohio. Undertab 26 comprises a smaller strip of the Technicote 60# semi-gloss paper, without adhesive, sandwiched between a portion of base 18 and a portion of laminate 28. Undertab 26 is consequently a non-pressure sensitive material. Laminate 28 is a standard 1 mil selfwound laminate made by Achem Industry America, Inc. of Los Angeles, Calif.

Referring to FIG. 3A, base 18 has an upper surface 18 a and a lower surface 18 b. A first region 28 a of laminate 28 is secured to upper surface 18 a of base 18 by a first layer of an emulsion acrylic adhesive 23 a. A second region 28 b of laminate is secured to undertab 26 by a second layer of emulsion acrylic adhesive 23 b. Undertab 26 is not adhered to base 18 at all. Adhesive layers 23 a, 23 b create a strong bond between base 18 and first region 28 a of laminate 28 and between second region 28 b of laminate 28 and undertab 26. The strong bonds substantially prevent undertab 26 from being removed from second region 28 b of laminate 28. The bonds also prevent first region 28 a of laminate 28 from being removed from base 18.

Undertab 26 is smaller in size than both laminate 28 and base 18 in that undertab 26 is generally around half of the size of either of laminate 28 and base 18. In the preferred embodiment of the invention, both laminate 28 and base 18 are circular in shape and undertab 26 comprises a semicircular member that is adhered to a semicircular second region 28 b of laminate 28. Undertab 26 and second region 28 b of laminate 28 form the pull tab 20 of seal 8. Pull tab 20 extends outwardly from upper surface 18 a of base 18 and pivots about a diagonal of the circular base 18. Because laminate 28 is flexible in nature, pull tab 20 can be pivoted through 180 degrees relative to upper surface 18 a of base 18. Pull tab 20 is utilized to remove base 18 from insert 14 as will be hereinafter described.

In accordance with another specific feature of the present invention, a layer of ultra-removable pressure sensitive adhesive 24 secures lower surface 18 b of base 18 to the upper surface of insert 14.

Seal 8 is applied to insert 14 to cover insert holes 16 during transit from the manufacturer to the reseller and ultimately to the user. An unknown time may transpire from the manufacture of the particulate material 22 to its use. Seal 8 keeps particulate material 22 uncontaminated and undisturbed during this time. When the user wishes to dispense particulate material 22 from container system 1, it is necessary to remove seal 8 so that holes 16 will be opened to allow particulate material 22 to flow therethrough.

FIGS. 4&5 show the first steps in the seal removal process. Pull tab 20 generally lays flat horizontally and parallel to upper surface 18 of base 18 prior to use. Pull tab 20 is grasped between finger and thumb and is pivoted into a position where tab 20 extends substantially at right angles to upper surface 18 a. The user begins to apply an upwardly directed pulling force on pull tab 20 in the direction of Arrow A. The force is applied in a direction opposite the seal's bond with insert 14. This, in turn, transfers the force to the weakest bond within seal 8, namely the bond between adhesive 24 and insert 14. It should be understood that seal 8 begins to break free from insert 14 in a region immediately beneath a line of connection point C (FIGS. 2 and 3A) of pull tab 20 and base 18. This line of connection C extends substantially along a diagonal of base 18. Consequently, seal 8 breaks free from insert 14 in a completely different manner to previously known seals which have typically had to be lifted away from an insert at a position somewhere along the peripheral edge of the seal.

FIG. 5 shows container seal system 1 after sufficient force has been applied to pull tab 20 to partially break the bond of the pressure sensitive adhesive layer 24 between seal 8 and insert 14. Seal 8 is approximately half removed from insert 14 in FIG. 5.

In FIG. 6, seal 8 has been completely separated from the upper surface of insert 14 because the bond between adhesive layer 24 and insert 14 has been fully broken by the application of force. The bond between the pressure sensitive adhesive layer 24 and insert 14 is weaker than the bond of the adhesive 23 between pull tab 20 and base 18. Consequently, force applied to the pull tab 20 breaks the weaker of the two bonds and results in seal 8 being removed from insert 14. Once released, seal 8 is moved distant from insert 14 as illustrated by arrow B. At this stage, holes 16 are completely unobstructed and opened and particulate material 22 may be dispensed through them.

It will be understood by those of ordinary skill in the art that a stronger adhesive is applied between the components that make up the seal 8 than is applied between the seal 8 and the insert 14. Thus, when force is applied to seal 8, that force will be transmitted to the weakest link in the system, i.e., to the bond between the seal and the insert. Consequently, any adhesives which permit the seal 8 to break cleanly away from the insert 14 without leaving adhesive residue or seal material adhered onto the upper surface of insert 14, may be used without departing from the spirit of the present invention.

Pull tab 20 is readily and easily grasped by the user because undertab 26 is not adhered to base 18. Additionally, because the tab 20 extends outwardly from an upper surface of seal 8 as opposed to a peripheral edge thereof, it is easily accessed by the user for grasping and its relatively large size makes it easy for the user to hold onto tab 20 during removal of seal 8. Furthermore, pull tab 20 extends outwardly from the upper surface of seal 8 and along a diagonal thereof and consequently, tab 20 is in the most easily accessed location within the recessed insert 14.

In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied there from beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed.

Moreover, the description and illustration of the invention is an example and the invention is not limited to the exact details shown or described. 

1. A seal for a container system, said seal comprising: a base having an upper and a lower surface; a laminate layer having a lower surface defining a first and a second region; an undertab; said undertab being smaller than either of the upper surface of the base and lower surface of the laminate layer; a first adhesive on the lower surface of the base adapted to form a releasable bond between the base and a container insert; a second adhesive disposed between the first region of the laminate layer and a portion of the upper surface of the base, said second adhesive forming a fixed bond between the laminate layer and the base.
 2. The seal as defined in claim 1, further comprising an adhesive disposed between and fixedly bonding the second region of the laminate layer to the undertab; whereby said bonded undertab and second region of the laminate layer form a pull tab for removing the base from the container insert.
 3. The seal as defined in claim 2, wherein the first adhesive forms a weaker bond between the base and the container insert than the bond formed by the second adhesive between the base and first region of the laminate layer.
 4. The seal as defined in claim 1, wherein the base and the laminate layer are generally circular in shape and the undertab is generally semicircular in shape.
 5. The seal as defined in claim 4, wherein the undertab is adhered to the laminate layer in such a manner that the pull tab is semi-circular in shape and is pivotable about a diagonal of the circular base.
 6. The seal as defined in claim 5, wherein the pull tab is pivotable through 180 degrees relative to the upper surface of the base.
 7. The seal as defined in claim 1, wherein the base is comprised of a pressure sensitive semi-gloss paper.
 8. The seal as defined in claim 1, wherein the laminate layer is comprised of a 1 mil selfwound laminate.
 9. The seal as defined in claim 1, wherein the undertab is comprised of a non-pressure sensitive semi-gloss paper.
 10. In combination: a container having a chamber adapted to receive a fine particulate material therein; said container defining an opening through which said chamber is accessible; an insert engageable in the opening of the container; said insert including a plurality of holes through which particulate material is dispensed from the chamber; a removable seal for obstructing said holes in the insert prior to use; said seal comprising: a base; a first adhesive applied between a lower surface of the base and the insert; a pull tab extending outwardly from an upper surface of the base; a second adhesive applied between the base and a portion of the pull tab; said second adhesive fixedly bonding said pull tab to the upper surface of the base; whereby application of an outwardly directed force to the pull tab breaks a bond between the first adhesive and the insert and permits the seal to be removed therefrom.
 11. The combination as defined in claim 10, wherein the seal further comprises a laminate layer having a first and second region; and an undertab; and wherein the second adhesive is applied between the first region of the laminate layer and the base, and between the second region of the laminate layer and the undertab; and wherein the undertab and second region substantially comprise the pull tab.
 12. The combination as defined in claim 11, wherein the pull tab extends outwardly away from an upper surface of the base.
 13. The combination as defined in claim 12, wherein the base is substantially circular in shape and the pull tab extends outwardly from the base along a diagonal thereof.
 14. The combination as defined in claim 13, wherein the pull tab is pivotable through 180 degrees about the diagonal.
 15. The combination as defined in claim 10, wherein the first adhesive is a pressure sensitive adhesive that forms a weaker releasable bond between the base and the insert.
 16. The combination as defined in claim 15, wherein the second adhesive is an emulsion acrylic adhesive that forms a strong non-releasable bond between the base and the pull tab.
 17. The combination as defined in claim 10, wherein the container comprises: a housing having a bottom wall, a peripheral side wall extending upwardly away from the bottom wall, and an upper wall terminating in a lip; and an interior chamber defined and surrounded by the bottom wall, side wall and upper wall; and wherein the lip defines the opening through which the chamber is accessible.
 18. The combination as defined in claim 17, wherein the insert comprises: an insert bottom wall; an insert peripheral side wall extending outwardly away from the insert bottom wall; and wherein the insert side wall is complementary sized and shaped to interlock with the lip of the container base when the insert is press-fitted into the opening.
 19. A method for sealing a container and removing said seal, said method comprising the steps of: applying a pressure sensitive adhesive side of a seal to an insert in a container to bond said seal to said insert, said seal being placed so that a plurality of holes in the insert holes are all located within an area covered by said seal; pivoting a pull tab that extends outwardly from an upper surface of said seal from a horizontal position to a substantially vertical position; applying a sufficient force to said pull tab to release the bond between said seal and said insert; and continuing to apply force to said pull tab until said seal is completely released from said insert. 